Phishing
An attempt to trick users into handing over credentials or money by impersonating a trusted entity.
Phishing typically arrives by email or SMS with a link to a convincing fake of a real login page. More sophisticated variants use sponsored ads on search engines, lookalike domains and stolen brand assets.
Ad blockers help by removing the ad-based delivery vector. Browsers add Safe Browsing-style warning lists. Password managers help by refusing to autofill on a domain that doesn't match the saved entry.